Birth of Healthy Children After Preimplantation Diagnosis of Thalassemias

Abstract

Background: Preimplantation genetic diagnosis (PGD) allows couples at risk of having children with thalassemia to ensure the healthy outcome of their pregnancy. Methods: Seventeen PGD clinical cycles were initiated for Cypriot couples at risk of having children with different thalassemia mutations, including IVS1-110, IVSI-6, and IVSII-745. Unaffected embryos for transfer were selected by testing oocytes, using first and second polar body (PB) removal and nested polymerase chain reaction analysis followed by restriction digestion. Results: Unaffected embryos were selected in 16 of 17 PGD cycles. Of 166 oocytes studied from these cycles, 110 were analyzed by sequential analysis of both the first and the second PB, resulting in preselection and transfer of 45 unaffected embryos. This resulted in seven pregnancies and in the birth of five healthy thalassemia-free children. The embryos predicted to have inherited the affected allele were not transferred. Analysis of these embryos confirmed the PB diagnosis. Conclusions: Sequential first and second PB testing of oocytes is reliable for PGD of thalassemia and is a feasible alternative to prenatal diagnosis in high-risk populations.